In Drosophila, Dichaete (D) is a mutation on chromosome III with a dominant effect on wing shape. It is lethal when homozygous. The genes ebony body (e) and pink eye (p) are recessive mutations on chromosome III. Flies from a Dichaete stock were crossed to homozygous ebony, pink flies, and the F1 progeny, with a Dichaete
- (a) Diagram this cross, showing the genotypes of the parents and offspring of both crosses.
- (b) What is the sequence and interlocus distance between these three genes?
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